1. Field of the Invention
The present invention relates to a drive mechanism suitable for conveying photosensitive material within a processing apparatus.
2. BACKGROUND INFORMATION
A processing apparatus, e.g. an automatic developing apparatus where an article to be processed is conveyed in processing tanks containing processing solution therein, is provided with a developing tank, a fixing tank and a washing tank which are box-shaped. A developing rack is placed in the developing tank. A fixing rack and a washing rack are similarly placed in the fixing tank and washing tank respectively. The developing rack, the fixing rack and the washing rack are each provided with an appropriate number of conveyor rollers, guides and the like.
The photosensitive material to be developed by such an automatic developing apparatus, is inserted through an insertion opening and conveyed for processing by conveyor rollers, guides and the like to the developing rack, the fixing rack, the washing rack, etc. for processing. After being washed by water in the washing tank, the photosensitive material is removed through an outlet after being dried in a drying section.
Conventionally, a motor has been employed as a driving source in this type of automatic developing apparatus. The driving force from the motor is transmitted to the conveyor rollers of each processing rack through a transmission shaft positioned adjacent to the vicinity of the upper portion of the processing rack. In other words, the transmission shaft is provided with a worm gear corresponding to each processing rack and the worm gear meshes a main gear placed on one side plate of each processing rack. Further, a driven shaft for supporting the main gear at its axis, crosses above the top of each tank so that the driving force can be transmitted, in turn, to a driven gear placed on the other side plate of each processing rack causing a plurality of conveyor rollers which convey the photosensitive material to rotate. In case such a drive mechanism comprising transmission shaft of the driving force, a driven shaft, a driven gear and the like is used, the drive mechanism is located above the upper portion of each tank so that the upper portion thereof is not completely enclosed, resulting in the disadvantage that air enters from the outside of tanks. Consequently, particularly in case of a developing tank, there has been the problem that oxidation of the developer is accelerated, since the developer accommodated in the developing tank reacts continuously with oxygen in the air.